Elastic fluid branch conduit structure



Oct. 25, 1960 H. R. REESE ET AL ELASTIC FLUID BRANCH CONDUIT STRUCTURE Filed March 13, 1959 2 Sheets-Sheet 1 REHEATER FIGI- J SI-IPRW REHEA TER T0 CONDENSER [ma l 3 INVENTORS HOMER R REE$E JAMES E.DONAHUE Oct. 25, 1960 H. R. REESE ETAL ELASTIC FLUID BRANCH CONDUIT STRUCTURE Filed March 13 1959 2 Sheets-Sheet 2 A p mm wm P MR mm on INVENTORS HOMER S.REE$E JAMES E.DONAHUE W Q25, 9

United States Patent ELASTKZ FLUID BRANCH CONDUIT STRUCTURE Homer R. Reese, Springfield, and James E. Donahue,

Media, Pa, assignors to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Filed Mar. 13, 1959, Ser- No. 799,259

Claims. (Cl. fill-70) This invention relates to fluid conducting apparatus, more particularly to elastic fluid conducting apparatus for receiving fluid from one turbine unit and for directing the fluid received therefrom to a plurality of other turbine units and has for an object to provide improved conduit structure of the above type which performs with high efiiciency and further reduces the number of conduits heretofore deemed essential in power plant installations.

In steam turbine power plants utilizing several turbine units connected to each other and fed by steam which is first directed into one unit and then exhausted therefrom and directed into the other units, considerable complications have arisen in the mechanical arrangement of heretofore employed conduits, and the resulting conduit array formed a highly complex mechanical maze, costly to manufacture and difficult to service, as well as being unsightly to the observer.

In view of the above it is a further object of the invention to provide a steam turbine power plant of the multiple tandem connected turbine unit type, wherein steam is conveyed from unit to unit with a reduced number of conduits, yet with a relatively high order of efiiciency.

In accordance with the invention, there is provided a main conduit structure having a plurality of branch inlet conduits and a plurality of branch outlet conduits for receiving the steam from one turbine unit and directing the steam thus received to the other units with a desired division of flow and with a minimum of flow losses due to turbulence and the like. The main conduit is preferably disposed generally parallel to the longitudinal axes of the turbine units and the branch inlets and outlets are disposed normal to the axis of the main conduit. Further, there is provided a flow guiding member in the main conduit between the two inlet conduits. The flow guiding member is inclined with the inner wall surface of the main conduit thereby to form, with the main conduit, a convergent flow passageway of gradually reducing cross-sectional area in downstream direction. Immediately upstream of the flow guiding memher there is provided a row of turning guide vanes for guiding the steam flow from the first inlet conduit into the main conduit. In a similar manner, there is provided a second row of turning guide vanes disposed downstream of the flow guiding member adjacent the outlet of the second inlet conduit for directing the steam issuing therefrom smoothly into the main conduit passageway. Both of the rows of guide vanes are disposed at an angle with the longitudinal axis of the main conduit. Hence, as the steam flows through the first inlet "ice conduit into the main conduit such flow is guided, by the flow guiding member to one side of the main conduit in the region wherein the steam is being directed into the main conduit by the second inlet conduit. Since the steam flow being directed into the main conduit by the second inlet conduit joins the, steam flow from the first conduit immediately downstream of the flow guiding member, and since both flows are substantially parallel to each other, such merging is eifected with relatively low fluid losses.

In a similar manner, the main conduit. is provided with a flow guiding member disposed between the first branch outlet conduit and the second branch outlet, conduit, which outlet conduits direct steam into a pairof turbine units which utilize steam at a lower pressure and temperature value than the first unit. The flow guide member is employed to divide the fiow from the main conduit to the two branch outlet conduits and is located between: the. first and second branch outlet conduits. However, in this instancewthe flow guide member is inclined with the inner wall of the main conduit in such a manner that it defines therewith a divergent flow passageway portion of increasing cross-sectional area in downstream direction.

A first row of turning guide vanes is provided upstream of the flow guide member for directing steam into the first branch outlet conduit and a second row of turning guide vanes is provided downstream of the flow guide for directing steam flow from the main conduit into the second steam outlet conduit.

With this arrangement, steam from the main conduit is divided by the flow guide member so that the optimum flow is directed from the main conduit into the first branch outlet conduit and the remainder of such flow is diffused in transit through the divergent passageway and directed from the main conduit to the second branch outlet conduit in a smooth and highly efiicient manner.

With the above arrangement, the main conduit new functions in the same manner as two separate main conduits have heretofore, so that the number of main conduits for any specific application is reduced to one-half.

The foregoing and other objects are elfected by the invention as will be apparent from the following description and claims taken in connection with the accompanying drawings, forming apart of this application, in which:

Fig. l is a schematic view showing the simplified flow circuit attained with the invention in a steam power plant installation wherein four turbine units are disposed in end-to-end relation.

Fig. 2 is a detailed plan view of the installation shown in Fig. 1;

Fig. 3 is an end view of the installation shown in Fig. 2, with the end turbine unit omitted;

Fig. 4 is an enlarged longitudinal sectional view through one of the main conduit structures illustrated in Fig. 2 and showing the invention; and

Figs. 5 and 6 are sectional views taken on lines V.V and VIVI of Fig. 4.

Referring to the drawings in detail, in Fig. 1 there is shown schematically a steam turbine power plant installation having a HP. unit 10, an I.P. unit 11 of the double opposed-flow type and two L.P. units 12 and 13 of the double opposed-flow type connected to each other in tandem or end-to-end relation and energizing a suitable load such as a generator 14, in a manner well known in the art.

the area encompassed by the base of the conical guide Steam from a suitable source is delivered to the HP. unit as indicated by the arrow 15, expanded therein and then exhausted therefrom through a pair of divided outlets 16. The steam flow through the outlets 16 is then directed through suitable reheater structure where it is reheated to a higher temperature and then directed to the center of the LP. unit 11, as indicated by the arrows 17. The steam flow then divides and flows in opposite directions through the LP. unit and is exhausted therefrom through a pair of branch conduits 18 at. the right-handend and a second pairof branch conduits 19 at the left-hand end. The steam exhausted through the upper branch conduits 18 and 19 is directed to a substantially straight main conduit structure 20 of circular cross section and subsequently directed therefrom through a first branch conduit 21. into the first L.P. unit 12 and through a second branch conduit 22 into the second L.P. unit 13; After flowing through the LP. units 12 and 13 in opposite directions, the steam is exhausted therefrom at .a plurality of points as indicated by the arrows 23, to a suitablecondenser (notshown).

The steam exhausted from the LP. unit through the lower branch conduits 18 and 19 is directed to another main conduit structure 24. Since the main conduit structures 20 and 24 may be substantially identical, only the upper main conduit structure will be described.

Referring now to Figs. 2 and 4, the main. conduit structure 20 is of suflicient length to overlie the LP. unit 1 1 and the two L.P. units 12 and 13 and is disposed in spaced relation therewith with its longitudinal axis generally parallel to the common longitudinal axis of the LP. and the LP. units. The branch conduits 18 and 19, hereinafter termed branch inlet conduits, are disposedin spaced parallel alignment with each other with their longitudinal axes normal to the longitudinal axis of the main conduit. Hence, as steam flows into the main conduit from the branch inlet conduits it must turn through a right angle. 7

In the main conduit 20, in the region intermediate the two branch inlet conduits 18 and 19, there is pro vided an elongated flow guiding member 27. The flow guide, member 27, as best shown in Figs. 4,- and 6, has its upstream end connected to the lower portion of the internal wall of the main conduit in the region immediately adjacent to teh connectionbetween the branch inlet conduit and the main conduit as indicated at 28, while its downstream end is connected to a wall portion 29 of the branch inlet conduit 19 projecting into the main conduit. This connection is indicated at 30. In the embodiment shown, the flow guide member 27 is of generally conical shape with its appex at 28, and its base at 30 so that it defines jointly with they internal wall of the main conduit a convergent fluid flow passageway portion 31 of gradually diminishing cross-sectional area in downstream direction. Further the flow guide member and the main conduit jointly define a crescentshaped throat 32 at the downstream end of the flow guide 7 member.

' 18 and the main conduit there is provided a row of turning guide vanes 33 for directing the steam flow smoothly from the branch inlet conduit into the main conduit, as indicated by the arrows '34. In a similar manner, there is provided a row'of turning guide vanes 35 intermediate the branch inlet conduit 19 and the main conduit for directing the steam into the main conduit as indicated by arrows 36. Both 'ofthe rows of guide vanes 33 and 35 are inclined with the longitudinal axis of the main conduit as well as the longitudinal axes of the branch inlet conduits 18 and 19, as seen in Fig. 4; However, the guide vanes 33 occupy the full cross-sectional area of the passageway in the main conduit while, as best shown in Fig. 5, the guide vanes 35 occupy only member 27. .;v r.

For simplification of analysis, the flow guide member 27 may be assumed to divide the main conduit passageway into two portions, one of which is a passageway portion 31, and a second portion 37. As seen in Fig. 6, the passageway portion 31 is of inverted crescent-shape and extends across the upper region of the main conduit, while the passageway portion 37 is of generally circular shape and is disposed in the lower region of the main conduit passageway:

In operation, as steam flows from the branch inlet conduit 18 into the main conduit 20, the flow is guided and turned through a right angle by the guide vanes smoothly and with relatively high efliciency. This flow is thence directed by the flow guide member 27 into the upper region of the main conduit with increasing velocity and reduction in pressure through the passageway portion 31 and the throat 32. Concurrently therewith, steam flowing through the branch inlet conduit 19 is directed into the main conduit by the flow guide vanes 35 and turned in a generally longitudinal direction along the lower passageway portion 37. Hence, the two fluid streams flow in generally stratified courses, thereby minimixing mixing losses and turbulence as they flow jointly downstream in the main conduit.

After the steam flows downstream through the circular portion 38 of the main conduit, it is subsequently directed therefrom by the branch outlet conduits 21 and 22 for utilization in the LP. units 12 and 13.

In a manner similar to that described above, a row of turning guide vanes 39 is disposed within the main passageway in the region adjacent the connection of the main conduit 20 and the branch outlet conduit 21. In a similar manner, there is provided a row of turning guide vanes 40 in the region adjacent the connection between the main conduit and the branch outlet conduit 22. As seen inFig. 4, the rows of guide vanes 39 and 40 are inclined at an angle of about 45 with the axis of the maintain conduit as well as the axes of the branch outlet conduits 21 and 22, respectively, so that steam flow is directed therethrough and turned through a right angle as indicated by the arrows 42 in a smooth and eflicient manner.

In the main conduit passageway intermediate the branch outlet conduits 21 and 22 there is provided a flow guide member 43. The flow guide member 43 may be identical in form to the flow guide member 27 defined previously in conjunction with the branch inlet conduits 18 and 19. However, it is effective to divide the main fluid flow and is disposed in the main conduit passageway in reverse relation relative to the flow guide member 27, so that its apex 44 is located downstream of its base 45, and its base is located immediately adjacent the guide vanes 39 and attached to an internally projecting wall portion 46 of the branch outlet conduit 21. Hence, the flow guide member 43, jointly with the internal wall of the main conduit 20, forms a divergent passageway portion 47 having a throat portion 48 of reduced crosssectional area at the upstream end. Although not specifically shown, it will be understood that the passageway portion 47 is of generally crescent-shape cross sec-. tion and extends across the upper region of the main conduit passageway, and a second passagewayrportion 49 is provided in the lower conduit portion. The passageway portion 47 is similar in shapeto the. passageway portion 31, the important diiference being thatrthe passageway portion 31 is convergent in downstream direction while the passageway.47 is divergent and gradually increases in cross-sectional area in downstream direction. In similarmanner, the lower passageway portion 49 is of the same shape and contiguous with passageway portion 37.

In operation, as the steam flows through the main conduit 20, the lower portion thereof is directed into the branch outlet conduit 21 while the upper portion thereof flows through the throat 48 into the divergent passageway and.

47. In the passageway 47 it undergoes a difiusing action, that is, an increase in pressure with attendant reduction in velocity, and is subsequently directed by the guide vanes 40 into the branch outlet conduit 22. Here again, the division of flow from the main passageway to the two branch outlets is attained with a high order of efiiciency and relatively low flow losses.

Since the main conduit structure 20 may be subjected to high thermal and fluid thrust forces in operation, it is desirable to provide thrust balancing mechanism 50 at the right-hand end and thrust balancing mechanism 51 at the left-hand end, which mechanisms may be connected to the main conduit 20 by tie rods 52 and 53 to flanges 54 and 55, respectively, in a manner well known in the art.

It will now be seen that the invention provides conduit structure wherein a plurality of streams of fluid may be directed to a common passageway and joined therein and then divided and directed therefrom to a plurality of passageways in a simple yet highly efficient manner, thereby permitting a reduction in the number of main conduits for conveying steam from one or more fluid utilizing units to a plurality of other fluid utilizing units.

It will further be seen that with this invention the conduit structure for power plant installations may be arranged in a manner lending symmetry and compactness to the power plant installation.

Although in the specification the main conduits 20 and 24 have been termed upper and lower, in the embodiment described and shown these conduits are actually in horizontally spaced side-by-side relation, as will be seen by reference to Fig. 3, with the branch inlets and outlets disposed in radial planes.

In the illustrated embodiments, the flow guide members 27 and 43 have been shown as conical, to form, with the internal wall of the main conduit, passageway portions of gradually varying cross section. However, the exact shape of the guide members 27 and 43 is not so limited and numerous other shapes may be utilized, in accordance with the invention, for guiding the steam flow through the main conduit. It is desirable, however, that the flow guide member 27 be formed to impart a con vergent shape to its associated passageway portion, while the flow guide member 43 be suitably shaped to impart a divergent shape to its associated passageway portion.

While the invention has been shown in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof.

What is claimed is:

1. A power plant comprising a plurality of turbines disposed adjacent each other, a main tubular conduit for conveying motive fluid, and a plurality of branch conduits connected to said main conduit and said turbines, said branch conduits including a first and a second branch conduit disposed adjacent each other and at an angle to the longitudinal axis of said main conduit, and a conical flow guide member disposed in said main conduit between said first and second branch conduits, said flow guide member having a conical surface portion inclined with the inner wall surface of said main conduit and an apex portion disposed in abutment with said inner wall surface, said conical surface together with said inner wall surface defining a throat of substantially crescent shape and a fluid flow passageway of varying cross-sectional area.

2. A power plant comprising a pair of turbines disposed adjacent each other and each having :a branch conduit for admitting motive fluid thereto, a main tubular conduit communicating with both of the branch conduits and having an internal wall defining a fluid passageway, and means for guiding the fluid flow through said main conduit, said means including a conical member disposed in said main conduit intermediate the branch conduits, said member having a conical portion converging at an 6 apex: portion, an upstream edge portion of said conicalportion defining a throat of substantially crescent-shape with said main conduit and said apex portion being disposed in substantial abutment with the internal wall of said main conduit.

3; A power plant comprising a pair of turbines disposed adjacent' each other and each having a branch conduit for admittingmotive fluid thereto, a main tubular supply conduit communicating with both of the branch conduits and having an internal wall defining a motive fluid passageway, said branch conduits having their central axes disposed at an angle to the longitudinal axis of said main conduit, means for guiding the fluid flow through said supply conduit, said means including a conical member disposed in said main conduit intermediate the branch conduits and inclined with the wall of said main conduit, said member having a conical upstream edge portion partially defining a crescent-shape throat of reduced cross-sectional area, said member having an apex portion disposed in an abutment with said main conduit and together with said main conduit defining a passageway portion of gradually increasing cross section in the direction of fluid flow, and means including a plurality of guide vanes disposed adjacent said throat, said vanes being effective to turn the motive fluid as it flows from said main conduit into one of said branch conduits.

4. A power plant comprising first and second turbines disposed adjacent each other, and first and second branch conduits for conveying motive fluid to said first and second turbines, a tubular main conduit communicating with said first and second branch conduits and having an internal wall defining a motive fluid passageway, said branch conduits having their central :axes disposed in substantially parallel planes disposed normal to the longitudinal axis of said main conduit, means for guiding and dividing the fluid flow through said main conduit including a conical member having a conical surface portion extending generally longitudinally Within said main conduit intermediate said branch conduits, said member having an upstream edge portion of said conical portion disposed adjacent said first branch conduit and dividing the fluid passageway into first and second passageway portions, said first passageway portion communicating with said first branch conduit and said second passageway portion having a substantially crescentshape and communicating with said second branch condui-t, and means including a plurality of turning vanes disposed in said first portion and arranged in a row inclined with the longitudinal axis of said main conduit.

5. A power plant comprising at least three steam turbines of the opposed-flow type disposed in end-toend relation, a main conduit disposed in spaced parallel relation with the common axis of said turbines and extending substantially the combined length of said turbines, a. pair of adjacent branch inlet conduits for exhausing steam from one of said turbines to said main conduit, a pair of adjacent branch outlets for conveying steam from said main conduit to the remaining two turbines, said inlet conduits being disposed in mutually spaced parallel relationship and communicating with said main conduit adjacent one end, said inlet conduits being disposed with their axes substantially normal to the axis of said main conduit, said outlet conduits being disposed in mutually spaced parallel relationship and communicating with said main conduit adjacent the other end, said outlet conduits being disposed with their axes substantially normal to the axis of said main conduit, a row of steam flow turning vanes disposed in said main conduit adjacent the connection of each of said inlet and outlet conduits, the rows of turning vanes being inclined with the axis of said main conduit, a first flow guide member of conical shape disposed intermediate and extending from one to the other of said inlet conduits, said first flow guide memher having a surface portion inclined with a portion of the internal wall of said main conduit and jointly there with defining a first steam flow passageway portion of gradually diminishing cross section in downstream direction, and a second flow guide member of conical shape disposed intermediate and extending from one 5' to-theother of said outlet conduits, said Second flow guide member having a surface portion inclinedwith a portion of the internal wall of said main conduit and jointly therewith defining a second steam flow passageway' portion of :gradually increasing cross section in 10 downstream direction.

References Citedin the file of this patent UNITEDSTATES PATENTS Allen Sept. 11, 1928 Froehlich Sept. 21, 1954 FOREIGN PATENTS Italy Aug. 20, 1935 UNITED STATES PATENT OFFICE CERTIFICATION OF CORRECTION Patent No, 2,957,313 October 25, 1960 Homer R, Reese et al.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 3, line 45, for "teh" read the column 4, line 23, for "mixing", first occurrence, read mizing line 38, for "maintain" read main column 6, line 20,

after "in" strike out "an",

Signed and sealed this 2nd day of May 19610 (SEAL) Attest- ERNEST W. SWIDER DAVID L, LADD Attesting Officer Commissioner of Patents 

